Global and domestic demand for fossil fuels continues to rise despite price increases and other economic and geopolitical concerns. As such demand continues to rise, research and investigation into finding additional economically viable sources of fossil fuels correspondingly increases. Historically, many have recognized the vast quantities of energy stored in oil shale, coal and tar sand deposits, for example. However, these sources remain a difficult challenge in terms of economically competitive recovery. Canadian tar sands have shown that such efforts can be fruitful, although many challenges still remain, including environmental impact, product quality, and process time, among others.
Estimates of world-wide oil shale reserves range from two to almost seven trillion barrels of oil, depending on the estimating source. Regardless, these reserves represent a tremendous volume and remain a substantially untapped resource. A large number of companies and investigators continue to study and test methods of recovering oil from such reserves.
Recent developments in oil shale processing include the In-Capsule® process where crushed oil shale is placed within an earthen impoundment and heated to remove hydrocarbons from the oil shale. This technology is generally described in U.S. Pat. No. 7,862,705. Produced hydrocarbons can be removed through various drain systems and collection systems. However, the earthen impoundment is designed to be left in place and substantially undisturbed upon completion of the removal process. Long term stability and elimination or reduction of environmental impacts can be an important consideration in design and operation of such a system.